struct ssd_part and struct node_descriptor seem to have essentially the
same purpose: tag a wlr_scene_node with some extra data indicating what
we're using it for.
Also, as with enum ssd_part_type (now lab_node_type), ssd_part is used
for several types of nodes that are not part of SSD.
So instead of the current chaining (node_descriptor -> ssd_part), let's
flatten/unify the two structs.
In detail:
- First, merge node_descriptor_type into lab_node_type.
- Add a separate view pointer in node_descriptor, since in the case of
SSD buttons we need separate view and button data pointers.
- Rename ssd_part_button to simply ssd_button. It no longer contains
an ssd_part as base.
- Add node_try_ssd_button_from_node() which replaces
node_ssd_part_from_node() + button_try_from_ssd_part().
- Factor out ssd_button_free() to be called in node descriptor destroy.
- Finally, get_cursor_context() needs a little reorganization to handle
the unified structs.
Overall, this simplifies the code a bit, and in my opinion makes it
easier to understand. No functional change intended.
- Rename `scaled_scene_buffer` to `scaled_buffer`. This makes it clear
that `scaled_{font,img,icon}_buffers` are implementations of it.
- Move the files from `src/common` to `src/scaled-buffer` as
`scaled_icon_buffer` heavily depends on `server` and `view` etc.
Our codebase for ssd scenes has grown with a lot of technical debts:
- We needed to call `ssd_get_part()` everywhere to get the scene node of a
ssd part. We then needed to cast it to `wlr_scene_rect` and
`wlr_scene_buffer`. This bloated our codebase and even blocked
duplicated button types in `<titlebar><layout>`.
- `ssd_get_part_type()` was a dirty hack. It compared parent, grandparent
and grandgrandparent of a node with each subtree in the ssd to get the
part type of the node.
To resolve this issues, this commit changes how ssd scenes are managed:
- Access scene rects and scene buffers just as a member of `struct ssd`.
- `ssd_part` is now a attachment to a scene node that can be accessed via
node_descriptor->data, with a new node-descriptor type
`LAB_NODE_DESC_SSD_PART`. `LAB_NODE_DESC_SSD_BUTTON` is unified into it.
Now the scene graph under ssd->tree looks like below. The parentheses
indicate the type of ssd_part attached to the node:
ssd->tree (LAB_SSD_NONE)
+--titlebar (LAB_SSD_PART_TITLEBAR)
| +--inactive
| | +--background bar
| | +--left corner
| | +--right corner
| | +--title (LAB_SSD_PART_TITLE)
| | +--iconify button (LAB_SSD_BUTTON_ICONIFY)
| | | +--normal close icon image
| | | +--hovered close icon image
| | | +--...
| | +--window icon (LAB_SSD_BUTTON_WINDOW_ICON)
| | | +--window icon image
| | +--...
| +--active
| +--...
+--border
| +--inactive
| | +--top
| | +--...
| +--active
| +--top
| +--...
+--shadow
| +--inactive
| | +--top
| | +--...
| +--active
| +--top
| +--...
+--extents
+--top
+--...
When hovering on SSD, `get_cursor_context()` traverses this scene node
from the leaf. If it finds a `ssd_part` attached to the node, it returns
`ssd_part_type` that represents the resizing direction, button types or
`Title`/`Titlebar`.
This is a common practice in C projects, which simply enforces that
each header must compile cleanly without implicit dependencies on
other headers (see also the previous commit).
This matches the behavior of the surrounding borders and will usually
cause resizing instead of triggering the button itself. This effect
is only really visible when using a border width settings of > 1.
Fixes#379
Support returning the following structs:
- view from LAB_NODE_DESC_VIEW or LAB_NODE_DESC_XDG_POPUP
- lab_layer_surface form LAB_NODE_DESC_LAYER_SURFACE
- lab_layer_popup from LAB_NODE_DESC_LAYER_POPUP
